But sprites and animated stuffs are some sort of 1bpp Spectrum graphics (with attributes) transferred into Mode0... probably with a CPU intensive process as the emulation (WinApe, option "find graphics"...) can't enable to find the graphics... (no pre-coded graphix). As a result we can seem ugly attributes and the Wide pixels of Mode0 can't do justice to the design of the varied aliens (on Speccy they manage to look quite good actually)
The use of the Hard-wired sprites is obvious : the target/cross-hair... but sadly the bullets use most of the rest of the HardSprites slots while less or different method could have been usedto let some extra Hardsprites slots for extra special effects.